Examine source code of Radianceext

{
  "browser_specific_settings": {
    "gecko": {
      "id": "{20fd2ccb-6c7c-4a81-8bd3-e8b59c6e0cae}"
    }
  },
  "manifest_version": 3,
  "name": "Radiance",
  "action": {
    "default_title": "LostTime",
    "default_popup": "popup.html"
  },
  "permissions": [
    "storage"
  ],
  "version": "1.0.3",
  "content_scripts": [
    {
      "matches": [
        "https://*.facebook.com/marketplace/*"
      ],
      "js": [
        "script.js"
      ]
    }
  ]
}